Launching system



Aug. 29, 1967 A. J. GRANDY LAUNCI'IING SYSTEM Filed 001:. 6, 1965 INVENTOR. ANDREW J. GRANDY BY: ZWM-J gQM ATTORNEY).

United States Patent Filed Oct. 6, 1965, Ser. No. 493,591 4 Claims. (Cl. 89--1.703)

ABSTRACT OF THE DISCLOSURE This invention is directed to a hi-low recoilless system for launching missile decoys or the like in which the housing forward portion has a non-rotatable piston responsive to pressure gas for launching one or more objects at high velocity and the housing rearward portion has an inwardly directed wall terminating in an exhaust nozzle. A pair of diametrically opposed internally threaded lugs are integral with and extend inwardly from the housing mid-portion. A high pressure propellant chamber of cylindrical contour, longitudinally adjustable within the housing, has a mid-length, annular threaded projection in threaded engagement with the lugs to define a low pressure chamber in the housing and surrounding the propellant chamber which is provided with ignition means on its closed rear wall. A rupturable disc normally closes an open forward wall of the propellant chamber to temporarily prevent fluid communication between the high and low pressure chambers. Longitudinal adjustment of the propellant chamber within the housing will provide a variable throat constriction between their respective rear walls adjacent the nozzle and enable a predetermined operative recoil balance to be obtained.

i The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon. I

This invention relates to launching systems, and more particularly, to a hi-low recoilless thrusting system for launching missile decoys or the like objects in which little or no reaction or recoil force is transmitted to the supporting structure.

The primary object of the invention is to provide launching apparatus for missile objects or masses thereof of varying weights in which there is a resulting minimum or negligible recoil force.

Another object of the invention is to provide such an apparatuswith means for promoting the impingement of hot gas upon objects being launched.

In one aspect of the invention a recoilless launching system has a housing, a forward portion of which contains pressure responsive launching means and a rearward portion of which has an inwardly directed wall terminating in an exhaust nozzle, threaded projection means extending inwardly from the housing, a high pressure propellant chamber of cylindrical contour smaller than the housing and having a closed rear wall and threaded lateral projection means engaging the housing means, and ignition means secured to the propellant chamber.

These and other objects, features and advantages will become more apparent from the following description and accompanying drawings in which:

FIG. 1 is a longitudinal view substantially broken away in section of a preferred launching system embodying the principles of the invention.

FIG. 2 is a transverse sectional view taken along line 22 of FIG. 1.

FIG. 3 is a sectional view taken along line 3-3 of FIG. 1.

In FIG. 1 the hi-low recoilless housing shown generally at 11, which with attached launching tube 18 extends transversely through wafer 10, embodies a low pressure chamber 12 that surrounds a high pressure propellant containing chamber 13 as will be described hereinafter. The housing tubular sidewall 14 is preferably of cylindrical contour with its forward portion 15 flared inwardly and thickened at its terminal threaded central opening 16 which receives the rear cylinder portion 17 of a launching tube shown generally at 18. Housing sidewall 14 is integral with an inwardly extending annular rear wall 19 that terminates with an outwardly flaring nozzle construction 20, the rear end 21 of which is closely fitted within wafer hole 23 that terminates with the radial edge 24 of wafer 10.

Diametrically opposed, inwardly extending lugs 26, 27 (FIGS. 1, 2) integral with sidewall 14 substantially midlength thereof, have their inner surfaces forward with threads 28, 28 to define interrupted thread means which receive a threaded hub or annulus 29 located on the outer surface of cylindrical sidewall 30 defining the high pressure propellant chamber 13. The closed cylinder rear wall 31, containing a central slot 31A for cylinder rotating, preferably has appropriately secured thereto an ignition means 32. The threaded forward open end 34 of cylinder 30 receives a suitably rupturable closure disc 33 normally positioned adjacent an outwardly projecting metering cap 35 containing a plurality of apertures 36 for controlling the rate of pressure gas flow from the high pressure chamber 13 to the low pressure chamber 12.

Upon ignition of the propellant in chamber 13, the gas I pressure developed therein is metered out cap apertures 36 after rupture of disc 33. The gas pressure, upon its entry in low pressure chamber 12 acts upon piston head 37 to transmit energy to the fragile decoy mass in a manner to be described, prior to exiting from the longitudinal annular chamber 12 past the variable throat or constricted area 25 and out the rearwardly directed nozzle 20. The effective area of constriction 25 is predetermined by appropriate longitudinal adjustment of high pressure cylinder 30 along housing threaded lugs 26, 27 such that the distance between the respective rear walls 31, 19 may be set to obtain a predetermined recoil balance for the system.

Where successive launching of decoy masses having different total weights is desired, appropriate settings for the throat will enable maintenance of system recoil balance.

The inner cylindrical surface 40 of launching tube portion 17 is provided with longitudinally extending peripheral grooves 41 in which mating projections on the piston head periphery slide until the head 37 abuts the inwardly directed annular flange or stop means 42, the piston rod 38 being slidably and sealingly mounted adjacent O-ring 43A in the central opening 43 of flange 42. Rapid forward movement of the piston rod will launch the abutting decoy mass 45 which has been positioned in the conical shaped cavity defined by the correspondingly shaped launching tube forward portion 46 which is closely fitted in conical hole 22 of wafer 10 that in turn terminates substantially at the forward radial surface 47 of wafer 10.

Various modifications, changes or alterations may be resorted to without departing from the scope of the invention as defined in the appended claims.

I claim:

1. In a hi-low recoilless system, for launching missile decoys or the like, having a housing, the forward portion of which contains non-rotatable means responsive to pressure gas for launching one or more objects at high velocity and the rearward portion of which has an inwardly directed wall construction terminating in an exhaust nozzle,

a pair of diametrically opposed lugs integral with and extending inwardly from said housing substantially mid-length thereof, said lugs each having their inner surfaces threaded to define interrupted thread means,

a high pressure propellant chamber of cylindrical contour'within said housing and having a continuous threaded lateral projection substantiallymid-length thereof in threaded engagement with said lugs to form a low pressure chamber in said housing surrounding said propellant chamber,

ignition means secured to a closed rear wall of said propellant chamber, and

a rupturable disc normally closing an open forward wall of said propellant chamber to temporarily prevent fiuid communication between said high and low pressure chambers,

so constructed and arranged that longitudinal adjustment of said propellant chamber within said housing will provide a variable throat constriction between their respective rear walls adjacent said nozzle and enable a predetermined operative recoil balance to be attained.

2. The arrangement set forth in claim 1 wherein a longitudinally apertured metering cap is secured to said propellant chamber immediately forward of said disc, said propellant chamber having external slot means for rotation thereof, and said non-rotatable means slidingly and sealingly mounted in said housing forward portion.

3. In a recoilless system, for launching missile decoys or the like, having a housing, a forward portion of which contains non-rotatable means responsive to pressure gas for launching one or more objects and a rearward portion of which has an inwardly directed wall terminating in an exhaust nozzle,

a pair of diametrically opposed lugs extending inwardly from said housing, said lugs each having their inner surfaces threaded to define interrupted thread means,

a high pressure propellant chamber having a closed sidewall of cylindrical contour, said sidewall having smaller dimensions than said housing, said chamber having a closed rear Wall and a continuous threaded lateral projection in threaded engagement with said lugs to form a low pressure chamber in said housing surrounding said propellant chamber,

ignition means secured to said propellant chamber, and

a rupturable disc, normally closing an open forward wall of said propellant chamber,

so constructed and arranged that longitudinal adjustment of said propellant chamber within said housing will provide a variable throat constriction between their respective rear walls adjacent said nozzle and enable a predetermined operative recoil balance to be attained.

4. In a recoilless thrusting system, for launching missile decoys or the like, having a housing, a forward portion of which contains means responsive to pressure gas for launching one or more objects and a rearward portion of which has an inwardly directed wall terminating in an exhaust nozzle,

threaded projection means extending inwardly from said housing,

a high pressure propellant chamber having a closed sidewall of cylindrical contour, said sidewall being smaller than said housing, said chamber having a closed rear wall and continuous threaded lateral projection means in threaded engagement with said housing projection means to form a low pressure chamber in said housing surrounding said propellant chamber,

ignition means secured to said propellant chamber, and

a rupturable disc normally closing an open forward wall of said propellant chamber,

so constructed and arranged that longitudinal adjustment of said propellant chamber within said housing will provide a variable throat constriction between their respective rear walls adjacent said nozzle and enable a predetermined operative recoil balance to be obtained.

References Cited UNITED STATES PATENTS SAMUEL W. ENGLE, Primary Examiner. 

1. IN A HI-LOW RECOILLESS SYSTEM, FOR LAUNCHING MISSILE DECOYS OR THE LIKE, HAVING A HOUSING, THE FORWARD PORTION OF WHICH CONTAINS NON-ROTATABLE MEANS RESPONSIVE TO PRESSURE GAS FOR LAUNCHING ONE OR MORE OBJECTS AT HIGH VELOCITY AND THE REARWARD PORTION OF WHICH HAS AN INWARDLY DIRECTED WALL CONSTRUCTION TERMINATING IN AN EXHAUST NOZZLE, A PAIR OF DIAMETRICALLY OPPOSED LUGS INTEGRAL WITH AND EXTENDING INWARDLY FROM SAID HOUSING SUBSTANTIALLY MID-LENGTH THEREOF, SAID LUGS EACH HAVING THEIR INNER SURFACES THREADED TO DEFINE INTERRUPTED THREAD MEANS, A HIGH PRESSURE PROPELLANT CHAMBER OF CYLINDRICAL CONTOUR WITHIN SAID HOUSING AND HAVING A CONTINUOUS THREADED LATERAL PROJECTION SUBSTANTIALLY MID-LENGTH THEREOF IN THREADED ENGAGEMENT WITH SAID LUGS TO FORM A LOW PRESSURE CHAMBER IN SAID HOUSING SURROUNDING SAID PROPELLANT CHAMBER, 